Abstract
Objective: To evaluate clinical risk factors, cervical fetal fibronectin (fFN), cervical length, and mean gray value assessment in predicting of preterm delivery (PTD) in patients with signs and/or symptoms of preterm labor (PTL).
Study design: One hundred and seventeen women with PTL between 24 and 34 weeks of gestation were included. Cervical swabs were tested for fFN using the rapid fFN assay. When 2-dimensional transvaginal ultrasound measurement of cervical length was completed, a region of interest (ROI) of constant size was defined in the midsection of the posterior wall, and the tissue-specific gray scale was determined. The end point were PTDs at <34 and <37 weeks of gestation.
Results: In univariate analysis, the three strongest predictors of spontaneous preterm birth <34 weeks were positive fFN (relative risk [RR] 8.9; 95% confidence interval [CI] 2.6–30.1), cervical length ≤2.5 cm (RR 6.9; 95% CI 1.6–29.7), and a low mean gray value of ≤5.97 (RR 7.9; 95% CI 2.3–27.2). Predictors significantly associated with spontaneous PTD at less than 37 weeks of gestation included previous PTD in multiparas (RR 3.9; 95% CI 1.6–9.5), positive fFN (RR 7.6; 95% CI 3.8–15.3), cervical length ≤2.5 cm (RR 2.6; 95% CI 1.4–5.1) and a low gray scale value of ≤6.54 (RR 4.5; 95% CI 2.3–8.9). In the final regression models used to predict spontaneous PTD <34 weeks and <37 weeks of gestation, both a positive fetal fibronectin (odds ratio [OR] 13.4; 95% CI, 2.5–72.1, P=0.003 vs. OR, 17.3; 95% CI 4.9–61.8, P<0.001) and a low gray scale value (OR 6.3 95% CI 1.3–29.4, P=0.02 vs. OR, 7.1; 95% CI 2–25.2, P=0.003) remained powerful predictors. The RRs of spontaneous PTD <37 weeks has been analyzed by a combination of these significant parameters. Low mean gray value ≤6.54 and negative fFN had a 10.3-fold (95% CI 2–74.5) increased risk of spontaneous preterm birth at <37 weeks. Combination of positive fFN and normal gray level (>6.54), had a higher increase risk of PTD (RR 18.1; 95% CI 4.4–76.7). When both factors were positive, the RR increases to 24.8 (95% CI 6.2–98.7).
Conclusions: Combined use of rapid fFN and cervical gray value analysis improves the diagnostic efficiency and allows identification of women at risk for preterm delivery and in need for further prophylactic/therapeutic intervention.
References
1 Adams MM, LD Elam-Evans, HG Wilson, DA Gilbertz: Rates of and factors associated with recurrence of preterm delivery. Jama283 (12) (2000) 1591Search in Google Scholar
2 Andersen HF, CE Nugent, SD Wanty, RH Hayashi: Prediction of risk for preterm delivery by ultrasonographic measurement of cervical length. Am J Obstet Gynecol163 (3) (1990) 859Search in Google Scholar
3 Berghella V, JE Tolosa, K Kuhlman, S Weiner, RJ Bolog-nese, RJ Wapner: Cervical ultrasonography compared with manual examination as a predictor of preterm deli-very. Am J Obstet Gynecol177 (4) (1997) 723Search in Google Scholar
4 Berkowitz GS: An epidemiologic study of preterm delivery. Am J Epidemiol113 (1) (1981) 81Search in Google Scholar
5 Bishop EH: Pelvic Scoring for Elective Induction. Obstet Gynecol24 (1964) 266Search in Google Scholar
6 Carey LC, PL Berbee, P Coyle, JC Philcox, AM Rofe: Zinc treatment prevents lipopolysaccharide-induced teratogenicity in mice. Birth Defects Res Part A Clin Mol Teratol67 (4) (2003) 24010.1002/bdra.10035Search in Google Scholar
7 Creasy RK: Preventing preterm birth. N Engl J Med325 (10) (1991) 727Search in Google Scholar
8 Creasy RK, BA Gummer, GC Liggins: System for predicting spontaneous preterm birth. Obstet Gynecol55 (6) (1980) 692Search in Google Scholar
9 Foxman EF, P Jarolim: Use of the fetal fibronectin test in decisions to admit to hospital for preterm labor. Clin Chem50 (3) (2004) 663Search in Google Scholar
10 Goffinet F, P Rozenberg, G Kayem, M Perdu, HJ Philippe, I Nisand: [The value of intravaginal ultrasonography of the cervix uteri for evaluation of the risk of premature labor]. J Gynecol Obstet Biol Reprod (Paris)26 (6) (1997) 623Search in Google Scholar
11 Goldenberg RL, JD Iams, BM Mercer, PJ Meis, A Moawad, A Das, et al.: The Preterm Prediction Study: toward a multiple-marker test for spontaneous preterm birth. Am J Obstet Gynecol185 (3) (2001) 643Search in Google Scholar
12 Goldenberg RL, T Tamura, Y Neggers, RL Copper, KE Johnston, MB DuBard, et al.: The effect of zinc supplementation on pregnancy outcome. Jama274 (6) (1995) 463Search in Google Scholar
13 Gomez R, M Galasso, R Romero, M Mazor, Y Sorokin, L Goncalves, et al.: Ultrasonographic examination of the uterine cervix is better than cervical digital examination as a predictor of the likelihood of premature delivery in patients with preterm labor and intact membranes. Am J Obstet Gynecol171 (4) (1994) 956Search in Google Scholar
14 Guzman ER, C Walters, CV Ananth, C O'Reilly-Green, CW Benito, A Palermo, et al.: A comparison of sonographic cervical parameters in predicting spontaneous preterm birth in high-risk singleton gestations. Ultrasound Obstet Gynecol18 (3) (2001) 204Search in Google Scholar
15 Hillier SL, RP Nugent, DA Eschenbach, MA Krohn, RS Gibbs, DH Martin, et al.: Association between bacterial vaginosis and preterm delivery of a low-birth-weight infant. The Vaginal Infections and Prematurity Study Group. N Engl J Med333 (26) (1995) 1737Search in Google Scholar
16 Iams J: Prevention of preterm birth. N Engl J Med338 (1) (1998) 5410.1056/NEJM199801013380110Search in Google Scholar
17 Iams JD, D Casal, JA McGregor, TM Goodwin, US Kreaden, R Lowensohn, et al.: Fetal fibronectin improves the accuracy of diagnosis of preterm labor. Am J Obstet Gynecol173 (1) (1995) 141Search in Google Scholar
18 Iams JD, RL Goldenberg, PJ Meis, BM Mercer, A Moawad, A Das, et al.: The length of the cervix and the risk of spontaneous premature delivery. National Institute of Child Health and Human Development Maternal Fetal Medicine Unit Network. N Engl J Med334 (9) (1996) 567Search in Google Scholar
19 Iams JD, RL Goldenberg, BM Mercer, A Moawad, E Thom, PJ Meis, et al.: The Preterm Prediction Study: recurrence risk of spontaneous preterm birth. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Am J Obstet Gynecol178 (5) (1998) 1035Search in Google Scholar
20 Jolly MC, N Sebire, J Harris, S Robinson, L Regan: Obstetric risks of pregnancy in women less than 18 years old. Obstet Gynecol96 (6) (2000) 962Search in Google Scholar
21 Leppert PC, SY Yu: Apoptosis in the cervix of pregnant rats in association with cervical softening. Gynecol Obstet Invest37 (3) (1994) 150Search in Google Scholar
22 Levkoff AH, M Westphal, MC Miller 3rd, Y Michel: Maternal risk factors in infants with very low birth weight. Obstet Gynecol60 (5) (1982) 612Search in Google Scholar
23 Lockwood CJ, AE Senyei, MR Dische, D Casal, KD Shah, SN Thung, et al.: Fetal fibronectin in cervical and vaginal secretions as a predictor of preterm delivery. N Engl J Med325 (10) (1991) 669Search in Google Scholar
24 Mercer BM, RL Goldenberg, A Das, AH Moawad, JD Iams, PJ Meis, et al.: The preterm prediction study: a clinical risk assessment system. Am J Obstet Gynecol174 (6) (1996) 1885 discussion 93–5Search in Google Scholar
25 Newton ER, J Piper, W Peairs: Bacterial vaginosis and intraamniotic infection. Am J Obstet Gynecol176 (3) (1997) 67210.1016/S0002-9378(97)70568-4Search in Google Scholar
26 Owen J, RL Goldenberg, RO Davis, KA Kirk, RL Copper: Evaluation of a risk scoring system as a predictor of preterm birth in an indigent population. Am J Obstet Gynecol163 (3) (1990):87310.1016/0002-9378(90)91086-RSearch in Google Scholar
27 Papiernik E, J Bouyer, J Dreyfus, D Collin, G Winisdorffer, S Guegen, et al.: Prevention of preterm births: a perinatal study in Haguenau, France. Pediatrics76 (2) (1985) 154Search in Google Scholar
28 Papiernik E, M Kaminski: Multifactorial study of the risk of prematurity at 32 weeks of gestation. I. A study of the frequency of 30 predictive characteristics. J Perinat Med2 (1) (1974) 30Search in Google Scholar
29 Peaceman AM, WW Andrews, JM Thorp, SP Cliver, A Lukes, JD Iams, et al.: Fetal fibronectin as a predictor of preterm birth in patients with symptoms: a multicenter trial. Am J Obstet Gynecol177 (1) (1997) 13Search in Google Scholar
30 Rizzo G, A Capponi, D Arduini, C Lorido, C Romanini: The value of fetal fibronectin in cervical and vaginal secretions and of ultrasonographic examination of the uterine cervix in predicting premature delivery for patients with preterm labor and intact membranes. Am J Obstet Gynecol175 (5) (1996) 1146Search in Google Scholar
31 Roberts AK, F Monzon-Bordonaba, PG Van Deerlin, J Holder, GA Macones, MA Morgan, et al.: Association of polymorphism within the promoter of the tumor necrosis factor alpha gene with increased risk of preterm premature rupture of the fetal membranes. Am J Obstet Gynecol180 (5) (1999) 1297Search in Google Scholar
32 Romero R, M Sirtori, E Oyarzun, C Avila, M Mazor, R Callahan, et al.: Infection and labor. V. Prevalence, microbiology, and clinical significance of intraamniotic infection in women with preterm labor and intact membranes. Am J Obstet Gynecol161 (3) (1989) 817Search in Google Scholar
33 Shiono PH, MA Klebanoff, BI Graubard, HW Berendes, GG Rhoads: Birth weight among women of different ethnic groups. Jama255 (1) (1986) 48Search in Google Scholar
34 Simpson WJ: A preliminary report on cigarette smoking and the incidence of prematurity. Am J Obstet Gynecol73 (4) (1957) 807Search in Google Scholar
35 Tekesin I, S Marek, L Hellmeyer, D Reitz, S Schmidt: Assessment of rapid fetal fibronectin in predicting preterm delivery. Obstet Gynecol105 (2) (2005) 280Search in Google Scholar
36 Tekesin I, L Hellmeyer, G Heller, A Romer, M Kuhnert, S Schmidt: Evaluation of quantitative ultrasound tissue characterization of the cervix and cervical length in the prediction of premature delivery for patients with spontaneous preterm labor. Am J Obstet Gynecol189 (2) (2003) 532Search in Google Scholar
37 Witkin SS, S Vardhana, M Yih, K Doh, AM Bongiovanni, S Gerber: Polymorphism in intron 2 of the fetal interleukin-1 receptor antagonist genotype influences midtrimester amniotic fluid concentrations of interleukin-1beta and interleukin-1 receptor antagonist and pregnancy outcome. Am J Obstet Gynecol189 (5) (2003) 1413Search in Google Scholar
38 Yu SY, CA Tozzi, J Babiarz, PC Leppert: Collagen changes in rat cervix in pregnancy–polarized light microscopic and electron microscopic studies. Proc Soc Exp Biol Med209 (4) (1995) 360Search in Google Scholar
©2005 by Walter de Gruyter Berlin New York
